Acquisitions - Luxoft Acquisition, Purchase Price Allocation (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jun. 14, 2019	Mar. 31, 2019
Business Acquisition [Line Items]
Goodwill	$ 6,003		$ 7,606
Luxoft Holding Inc.
Business Acquisition [Line Items]
Cash and cash equivalents		$ 113
Accounts receivable		233
Other current assets		15
Total current assets		361
Property and equipment		31
Intangible assets	$ 571	571
Other assets		96
Total assets acquired		1,059
Accounts payable, accrued payroll, accrued expenses, and other current liabilities		(119)
Deferred revenue		(8)
Long-term deferred tax liabilities and income tax payable		(86)
Other liabilities		(68)
Total liabilities assumed		(281)
Net identifiable assets acquired		778
Goodwill		1,245
Total estimated consideration transferred		$ 2,023